This relates to communication networks, and more particularly, to communication networks having network switches that are controlled by a controller.
Packet-based networks such as the Internet and local data networks that are connected to the internet include network switches. Network switches are used in forwarding packets from packet sources to packet destinations. The packets may be sometimes referred to as frames. For example, data is forwarded over layer 2 of the Open Systems Interconnection (OSI) model as frames (e.g., Ethernet frames), whereas data is forwarded over layer 3 of the OSI model as packets (e.g., Internet Protocol packets).
It can be difficult or impossible to configure the switches of one vendor using the equipment of another vendor. This is because the switch equipment of one vendor may use a different operating system and set of control procedures than the switch equipment of another vendor. To address the challenges associated with controlling different types of switch platforms, cross-platform protocols have been developed. These protocols allow centralized control of otherwise incompatible switches.
Cross-platform controller clients can be included on the switches in a network. The controller clients are able to communicate with a corresponding controller server over network paths. Because the controller clients can be implemented on a variety of switch hardware, it is possible for a single controller to control switch equipment that might otherwise be incompatible.
It can be challenging for a controller to ensure that switches are successfully configured as the controller intended. Consider the scenario in which a controller provides thousands of control packets to a switch, but the switch processing capacity is insufficient to process the control packets at the rate they are provided by the controller. As another example, configuration storage capacity at a switch may be filled and the switch may be incapable of storing any additional configuration data without overwriting existing configuration data. As yet another example, a new switch may connect or an existing switch may disconnect from the network, which may lead to mismatch between the controller's view of the network and the actual configuration state of the network.